Abstract
In this paper, a new modal parameters identification method is presented based on NExT (natural excitation technique) and the response data of the structure under non-stationary ambient excitation the white noise excitation assumption for NExT is extended to a MA (q) model assumption to establish an extended NExT method. Then the assumption that the non-stationary excitation is composed of a (d-1)-th order polynomial and a MA(q) model is proposed. Taking d-th order difference of the non-stationary excitation yields a MA(q+d) model, which satisfies the assumption of the extended NExT method mentioned above. Thus, the extended NExT method can be used in the condition of non-stationary excitation. In order to reduce the error of difference calculation during identification implementation, the difference computation is performed in frequency-domain instead of time-domain. The identification results from the proposed method are compared with the standard NExT for a three DOFs (degrees of freedom) vibration system and the finite element (FE) model of Longtanhe Bridge. The results show that the method proposed in this paper can obtain better modal parameters of the system under non-stationary ambient excitation than the standard NExT.
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References
Zheng, D., Li, Z.: A new development of modal parameter identification based ambient excitation. Journal of Test and Measurement Technology 16, 1439–1447 (2002) (in Chinese)
Xu, X., Hua, H., Chen, Z.: Review of modal identification method based on ambient excitation. Journal of Vibration and Shock 21(3), 1–5 (2002) (in Chinese)
Peeters, B., De Roeck, G.: Stochastic subspace techniques applied to parameter identification of civil engineering structures. In: Proceeding of New Advances in Modal Synthesis oj Large Structure: Nonlinear, Damped and Nondeterministic Cases, Lyon, France, pp. 151–162 (September 1995)
Peeters, B., De Roeck, G.: Reference based stochastic subspace identification in civil engineering. Inverse Problems in Engineers 8, 47–74 (2000)
Zhang, Z.Y., Hua, H.X., Xu, X.Z., Huang, Z.: Modal parameter identification through Gabor expansion of response signals. Journal of Sound and Vibration 266, 943–955 (2003)
Bonata, P., Ceravolo, R., De Stefano, A.: Time-frequency and ambiguity function approaches in structural identification. Journal of Engineering Mechanics 123(12), 1260–1267 (1997)
Bonato, P., Ceravolo, R., De Stefano: Use of cross-time-frequency estimators for structural identification in non-stationary conditions and under unknown excitation. Journal of Sound and Vibration 237(5), 775–791 (2000)
Li, Z., Hua, H.: Modal parameters identification of linear structrures undergoing non-stationary ambient excitation. Journal of Vibration and Shock 27(3), 8–12 (2008) (in Chinese)
James, G.H., Carne, T.G., Lauffer, J.P.: The natural excitation technique for modal parameter extraction from operating wind turbines, Rep. No. SAND92-1666, UC-261. Sandia National Laboratories, Sandia
James, G.H., Carne, T.G., Mayes, R.L.: Modal parameter extraction from large operating structures using ambient excitation. In: Proc. of 14th Int. Modal Analysis Conf., Dearborn, Mich
Farrar, C.R., James III, G.H.: System identification from ambient vibration measurements on a bridge. Journal of Sound and Vibration 205(1), 1–18 (1997)
Shen, F., Zheng, M., Feng Shi, D.: Using the cross-correlation technique to extract modal parameters on response-only data. Journal of Sound and Vibration 259(5), 1163–1179 (2003)
Caicedo, J.M., Dyke, S.J., Johnson, E.A.: Natural excitation technique and eigensystem realization algorithm for phase I of the IASC-ASCE Benchmark problem: simulated data. Journal of Engineering Mechanics, 49–60 (January 2004)
Wang, Y.: Applied time series analysis. University of China Press, Beijing (2000) (in Chinese)
Hu, G.: Digital signal processing, 2nd edn. Tsinghua University Press, Beijing (2003) (in Chinese)
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Xiang, L., Lu, Q. (2012). Modal Parameter Identification of Linear Time Invariant System under Non-stationary Ambient Excitation. In: Ni, YQ., Ye, XW. (eds) Proceedings of the 1st International Workshop on High-Speed and Intercity Railways. Lecture Notes in Electrical Engineering, vol 148. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-27963-8_23
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DOI: https://doi.org/10.1007/978-3-642-27963-8_23
Publisher Name: Springer, Berlin, Heidelberg
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